Milk yields from first, second and third lactation dairy cows differ substantially.
We hypothesize that their rumen microbiomes will be concomitantly different.
Microbial ecology of younger dairy cows were different to that of older cows.
Rumen microbial shifts were independent by age and diet in the rumen of dairy cows.
The abundance of amylolytic enzymes on starch rich diets was noteworthy.